The present invention relates to a method of securing a trailing end of a web in a web roll to a surface of the web roll in a slitter-winder with least one attachment article having an adhesive surface which extends over the trailing end of the web and onto the roll surface.
The present invention relates also to an arrangement for securing a trailing end of a web in a web roll to a surface of the web roll in a slitter-winder by setting at least one attachment article to extend over a trailing end of the web on the roll surface.
It is known that paper is manufactured in machines, which together constitute a paper-manufacturing line, which can be hundreds of meters long. Modern paper machines can produce over 450,000 tons of paper per year. The speed of the paper machine can exceed 2,000 m/min and the width of a paper web can be more than 11 meters.
In paper-manufacturing lines, the manufacture of paper takes place as a continuous process. The paper web completing in the paper machine is wound by a reel-up around a reeling shaft, i.e. reel spool, into a parent roll, the diameter of which can be even more than 5 meters and a weight of more than 160 tons. The purpose of winding is to modify the paper web manufactured as planar into a more easily processable form. On the reel-up located in the main machine line, the continuous process of the paper machine breaks for the first time and shifts into periodic operation. This periodicity is tried to be made with efficiency as good as possible in order not to waste already done work. This applies also to pulp drying machines where the dried pulp is reeled instead of cut into pulp sheets, of which pulp bales are formed.
By means of slitter-winders, a full-width web is cut in the longitudinal direction to partial webs on the cutting section and the partial webs are wound to customer rolls on the windup section. In windups, the partial webs are wound around cores to fiber web rolls and the longitudinal successive cores are locked in place to a core array by means of a core-locking device located at both ends. So called carrier roll windups are widely used in the slitter-winder, in which the partial webs are wound carried by two carrier rolls to partial web rolls via a nip between a second carrier roll and a fiber-web roll being formed. Also a belt arrangement i.e. a so-called set of belt rolls located around leading rolls can be used as the carrier roll.
In the slitter-winder in winding a fiber web, a set change means a stage in which when manufacturing rolls always before starting a new winding the winding has to be stopped, the web to be cut by the windup and the set i.e. completely wound rolls to be removed and after setting new cores the winding of the new set i.e. partial web rolls to be completed next to start again. Nowadays, the set change time in web winding is, in practice, when using machine arrangements, around 30-70 seconds from stopping the winding to its restarting.
It is known as such to use adhesive tape for securing the ends of the set of rolls. This requires a great number of so called tape dispensers arranged cross directionally the windup. Usually at least two dispensers per web roll are needed in order safely to secure the ends of the roll. Further, the tape dispensers have to be mounted on a common carrier at a suitable distance from one another corresponding to the widths of the web rolls and, in case the width of the rolls is changed, the dispensers must be positioned again to meet the new configuration.
WO 2007060293 A2 discloses a method of attaching the end of the web to the surface of the web roll by means of glue. Glue is advantageous as such and it is easy to provide automated procedures to apply glue on the web. Particularly, WO 2007060293 A2 discloses a method in winding a fiber web in connection with the set change of a slitter-winder, in which the web is cut by a cutting blade, the tails of partial webs are fastened to web rolls, completed partial web rolls are removed by means of a roll pusher and new cores are transferred to the support of the carrier rolls. In the method, when removing the completed partial web roll from the slitter-winder by the roll pusher, the main tail part of a glue stripe formed by glue applied to the end of the web is pressed finally fast in a nip between the roll pusher and the partial web roll. Respectively, the document discloses also to a device in winding a fiber web in connection with the set change of a slitter-winder, which device is arranged into connection with a carrier roll windup, which carrier roll windup comprises a rear carrier roll and a front carrier roll, carried by which the partial webs cut to partial webs by the slitter winder are wound to partial web rolls around winding tubes i.e. cores. The device comprises a roll pusher, which roll pusher is arranged to push the roll out of the windup forming a nip between the roll pusher and the completed partial web roll for the final compression of the glue stripe applied to the tail of the partial web roll. Using glue for attaching of the end of the web on the roll easily deteriorates the outer layers of the roll.
EP 0 553 232 B1 discloses a method of effecting a set change in a winder wherein the web cross-cutting apparatus and the adhesive activation apparatus are located upstream of the first winder drum, and the web severance is after the skip-slitting operation. There is also disclosed a method for cross-cutting the paper web utilizing a skip-slitting laser, applying an adhesive to the trailing and leading edges of the cross-cut paper web, and applying the trailing end to the previously wound roll and the leading edge to a new core.
Both of the above examples of prior art are also such that the end of the web is attached to the roll in the windup itself. During the time the finished rolls are still in the windup, it is impossible to start winding of the new set of rolls. Therefore these kinds of solutions are not as effective as possible.
An object of the invention is to provide a method of and arrangement for securing a trailing end of a web in a web roll in which the overall performance is considerably improved compared to the prior art solutions.